<template>
  <div id="home" class="wrapper">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
    <tab-control ref="tabControl1"
                 :titles="['流行', '新款', '精选']"
                 @tabClick="tabClick"
                 class="tab-control"
                 v-show="isTabFixed"
    />
    <scroll class="content" ref="scroll" :probe-type="3" @scroll="contentScroll"
             :pull-up-load="true" @pullingUp="loadMore" >
    <home-swiper :banners="banners" @swiperImageLoad="swiperImageLoad"/>

    <recommend-view :recommends="recommends"></recommend-view>

    <feature-view></feature-view>

    <tab-control ref="tabControl"
                 :titles="['流行', '新款', '精选']"
                 @tabClick="tabClick"
               />

    <good-list :goods="showGoods"/>
    </scroll>

    <back-top @click.native="backClick" v-show="isShowBackTop"/>
  </div>

</template>

<script>
import NavBar from '@/components/common/navbar/NavBar'
import {getHomeMultidata,getHomeGoods,getHomeMultidata11} from '@/network/home'
import HomeSwiper from './childComps/HomeSwiper'
import RecommendView from './childComps/RecommendView'
import FeatureView from './childComps/FeatureView'
import TabControl from '../../components/content/tabControl/TabControl'
import GoodList from '../../components/content/goods/GoodsList'
import Scroll from '../../components/common/scroll/Scroll'
import BackTop from '../../components/content/backTop/BackTop'
import {itemListenerMixin} from '../../common/mixin'

export default {
  name: 'Shouye',
    components:{
      BackTop,
      NavBar,
      HomeSwiper,
      RecommendView,
      FeatureView,
      TabControl,
      GoodList,
      Scroll
    },
  mixins:[itemListenerMixin],
  data(){
    return{
     // result:null
      banners:[],
      recommends:[],
      goods:{
        'pop':{page:0,list:[]},
        'new':{page:0,list:[]},
        'sell':{page:0,list:[]}
      },
      currentType: 'pop',
      isShowBackTop: false,   //让移至顶部不出现
      tabOffsetTop:0,
      isTabFixed:false,
      saveY:0
    }
  },
  computed: {
    showGoods() {
      return this.goods[this.currentType].list
    }
  },
  activated(){
   this.$refs.scroll.scrollTo(0,this.saveY,0)
   this.$refs.scroll.refresh()
  },
  deactivated(){
    this.$bus.$off('itemImgLoad',this.itemImgListener)
    this.saveY=this.$refs.scroll.getScrollY()
  },
  created () {
    // 1.请求多个数据
    this.getHomeMultidata()
    //2.请求商品数据
    this.getHomeGoods('pop')
    this.getHomeGoods('new')
    this.getHomeGoods('sell')

  },
  methods: {
    /**
     * 事件监听相关的方法
     */
    debounce(func,delay){//防止刷新过多次，防抖动
       let timer=null;
      return function (...args){
        if(timer) clearTimeout(timer)
        timer =setTimeout(() =>{
          func.apply(this,args)
        },delay)
      }
    },
    tabClick(index) {
      switch (index) {
        case 0:
          this.currentType = 'pop'
          break
        case 1:
          this.currentType = 'new'
          break
        case 2:
          this.currentType = 'sell'
          break
      }
      this.$refs.tabControl.currentIndex=index;
      this.$refs.tabControl1.currentIndex=index;
    },
    backClick() {
      this.$refs.scroll.scrollTo(0, 0)
    },
    contentScroll(position) {
      //判断backtop是否显示
      this.isShowBackTop = (-position.y) > 1000
    // 决定tabControl是否吸顶（position：fixed）
      this.isTabFixed = (-position.y) > (this.tabOffsetTop+44)
    },
    loadMore() {
      this.getHomeGoods(this.currentType)
    },
    swiperImageLoad(){
      //获取tabControl的offsetsetTop值
      //所有组件都有一个属性$el：用于获取组件中的元素
     this.tabOffsetTop= this.$refs.tabControl.$el.offsetTop

    },
    /**
     * 网络请求相关的方法
     */
    getHomeMultidata() {
      getHomeMultidata().then(res => {
        // this.result = res;
        this.banners = res.data.banner.list;
        this.recommends = res.data.recommend.list;
      })
    },
    getHomeGoods(type) {
      const page = this.goods[type].page + 1
      getHomeGoods(type, page).then(res => {
        this.goods[type].list.push(...res.data.list)
        this.goods[type].page += 1
        //完成上拉加载更多
        this.$refs.scroll.finishPullUp()
        this.$refs.scroll.refresh()
      })
    }
  }
}
</script>

<style>
#home{
  position: relative;
  height: 100vh;
  /*padding-top: 44px;*/
}
.home-nav{
  background-color: var(--color-tint);
  color: #fff;
  /*position: fixed;*/
  /*left: 0;*/
  /*right: 0;*/
  /*top: 0;*/
  /*z-index: 9;*/
}
.tab-control{
  position: relative;
  z-index: 9;
  padding-top: 0px;
  overflow: hidden;
  top:-1px;
}
.content{
 position: absolute;
  overflow: hidden;
  top: 44px;
  left: 0px;
  right: 0px;
  /*bottom: 49px;*/
}
</style>
